i don't have much clue on how this got activated, but it's there and somehow working:
http://img825.imageshack.us/img825/3897/byg.png
From here you can see that my Chimaera pet has 8 days remaining on its Bestial Wrath - Bestial Wrath - Spell - World of Warcraft
Now this isn't just a display bug, but it's an actual extension of the buff. Along with the glyph: Glyph of Endless Wrath - Spell - World of Warcraft - Your pet is basically immortal.
I tried killed myself, having the pet active - That did NOT remove the buff.
Tried getting the pet killed (whilst glyph was on) - Pet stayed on 1hp.
Watched logs, all pet dmg abilities were doing 20% more dmg.
The only thing that removes the buff is that if you reapply it with the 10 second duration buff of BW.
PET HISTORY:
From the moment i tamed the pet, it has only been out of the stables twice, for a maximum amount of time of 2 hours.
It has been stabled over the time of atleast 6 days of suspensions.
it has been stabled along with atleast 3 race/fac changes and atleast 1 migration.
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The huge potential lies in that the buff is 8 days long, aka your pet cannot die for 8 days which basically means that you can have it to tank anything and it wont die.
If used nicely you can have it to tank all the bosses of ToT(given it keeps threat) and fully replace your tanks.
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Entering BG's Arenas etc will remove pet buffs.
If you got any clue on how this works feel free to comment.